2o6p: Difference between revisions
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== | ==Crystal Structure of the heme-IsdC complex== | ||
<StructureSection load='2o6p' size='340' side='right'caption='[[2o6p]], [[Resolution|resolution]] 1.50Å' scene=''> | |||
[ | == Structural highlights == | ||
[ | <table><tr><td colspan='2'>[[2o6p]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Staphylococcus_aureus_subsp._aureus_N315 Staphylococcus aureus subsp. aureus N315]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2O6P OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2O6P FirstGlance]. <br> | ||
[ | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.5Å</td></tr> | ||
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr> | |||
[ | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2o6p FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2o6p OCA], [https://pdbe.org/2o6p PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2o6p RCSB], [https://www.ebi.ac.uk/pdbsum/2o6p PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2o6p ProSAT]</span></td></tr> | ||
[[ | </table> | ||
[ | == Function == | ||
[[ | [https://www.uniprot.org/uniprot/ISDC_STAA8 ISDC_STAA8] Involved in heme (porphyrin) scavenging. Binds hemoglobin and almost exclusively free-base protoporphyrin IX. Probably has a role as the central conduit of the isd heme uptake system, i.e. mediates the transfer of the iron-containing nutrient from IsdABH to the membrane translocation system IsdDEF. Hemin-free IsdC (apo-IsdC) acquires hemin from hemin-containing IsdA (holo-IsdA) probably through the activated holo-IsdA-apo-IsdC complex and due to the higher affinity of apo-IsdC for the cofactor. The reaction is reversible (By similarity).<ref>PMID:15240116</ref> <ref>PMID:17287214</ref> | ||
[ | == Evolutionary Conservation == | ||
[[Image:Consurf_key_small.gif|200px|right]] | |||
Check<jmol> | |||
<jmolCheckbox> | |||
<scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/o6/2o6p_consurf.spt"</scriptWhenChecked> | |||
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | |||
<text>to colour the structure by Evolutionary Conservation</text> | |||
</jmolCheckbox> | |||
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=2o6p ConSurf]. | |||
<div style="clear:both"></div> | |||
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== Publication Abstract from PubMed == | |||
Pathogens such as Staphylococcus aureus require iron to survive and have evolved specialized proteins to steal heme from their host. IsdC is the central conduit of the Isd (iron-regulated surface determinant) multicomponent heme uptake machinery; staphylococcal cell-surface proteins such as IsdA, IsdB, and IsdH are thought to funnel their molecular cargo to IsdC, which then mediates the transfer of the iron-containing nutrient to the membrane translocation system IsdDEF. The structure of the heme-IsdC complex reveals a novel heme site within an immunoglobulin-like domain and sheds light on its binding mechanism. The folding topology is reminiscent of the architecture of cytochrome f, cellobiose dehydrogenase, and ethylbenzene dehydrogenase; in these three proteins, the heme is bound in an equivalent position, but interestingly, IsdC features a distinct binding pocket with the ligand located next to the hydrophobic core of the beta-sandwich. The iron is coordinated with a tyrosine surrounded by several non-polar side chains that cluster into a tightly packed proximal side. On the other hand, the distal side is relatively exposed with a short helical peptide segment that acts as a lip clasping onto almost half of the porphyrin plane. This structural feature is argued to play a role in the mechanism of binding and release by switching to an open conformation and thus loosening the interactions holding the heme. The structure of the heme-IsdC complex provides a template for the understanding of other proteins, such as IsdA, IsdB, and IsdH, that contain the same heme-binding module as IsdC, known as the NEAT (near transporter) domain. | |||
Crystal structure of the heme-IsdC complex, the central conduit of the Isd iron/heme uptake system in Staphylococcus aureus.,Sharp KH, Schneider S, Cockayne A, Paoli M J Biol Chem. 2007 Apr 6;282(14):10625-31. Epub 2007 Feb 7. PMID:17287214<ref>PMID:17287214</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
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<div class="pdbe-citations 2o6p" style="background-color:#fffaf0;"></div> | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Large Structures]] | |||
[[Category: Staphylococcus aureus subsp. aureus N315]] | |||
[[Category: Cockayne A]] | |||
[[Category: Paoli M]] | |||
[[Category: Schneider S]] | |||
[[Category: Sharp KH]] | |||